The short answer
On a fan oven the ring element behind the back panel does most of the heating, so the fastest diagnosis is to compare programmes. Fan settings failing while conventional settings work is a ring element, and that is a very common fault.
What you actually see and hear
- Fan programmes do not heat but conventional settings do — The ring element behind the rear panel has failed.
- The fan turns but the air stays cold — Same conclusion - the fan is fine and the element around it is not.
- Everything heats slowly and never holds temperature — A sensor reading wrongly, or heat escaping past the door.
- The oven is completely cold and the display is dark — Power, not heating. Start at the breaker.
- NEAR MISS - the oven smells hot when first used after cleaning — Residue burning off. Normal and short-lived.
Causes, most likely first on this machine
- Fan ring element failed — First on a fan oven and the single most common heating fault on this class. It fails open with age and takes every fan programme with it.
- Conventional bake or grill element failed — Second. If one works and the other does not, you have localised it without any tools.
- Oven temperature sensor drifted — Third. It makes the oven run cool or cycle wrongly rather than stay stone cold.
- Door seal or dropped door losing heat — Fourth, and easy to underestimate: a heat leak into the cabinet makes a healthy oven look weak.
- Control relay or board — Fifth, and it is what remains after the elements and the sensor.
- Supply loss on one side of the circuit — Last, but distinctive: some functions work and others do not, with no element actually faulty.
Check in this order, and why
- Run each programme in turn and note which heat — Fan versus conventional versus grill localises the fault immediately.
- Watch a preheat with the oven light on — A glowing element is a working element.
- Put an oven thermometer in and compare with the setting — A consistent offset is a sensor signature.
- Check the door for droop and the gasket for flat sections — A heat-leaking door imitates a weak oven.
What an owner can safely check
- Run a short preheat on each programme and note the result — This costs nothing and it is the most useful information there is.
About 45 min
- Let the oven cool and inspect the visible elements — Look for a break, blistering or a scorched section.
Tools: torchAbout 15 min
- Put an oven thermometer in at a mid setting and let it settle — Compare the reading with the setting before concluding anything.
Tools: oven thermometerAbout 45 min
- Check the door gaps at top and bottom and the gasket condition — Heat leaking into the cabinet is a real and common contributor.
Tools: paperAbout 15 min
- Check the breaker has not tripped on one side of a split supply — Some functions working and others not can be a supply issue.
About 10 min
- STOP HERE before removing the rear cavity panel to reach the ring element — That is live work and it means drawing the oven out of its housing.
Before you open anything
Safety
Switch the oven off at its breaker before touching anything - a built-in oven is wired into a dedicated circuit and there is no plug to pull. Let the cavity cool completely first; a fan oven holds heat in the cabinet long after the door is opened. If the appliance is part of a gas installation and you smell gas, do not switch anything on or off, leave the building, and call the gas utility from outside.
When to call a technician
Call a technician when fan programmes fail and conventional ones work, because that is the ring element behind the rear panel - an ordinary repair, but one that needs the oven drawn out. Call an electrician if part of the supply has been lost. Mention which programmes work when you book, since it tells the technician which part to bring and can turn two visits into one.
Nearest pages of this class
What this page does not cover
This page is written for the built-in fan oven class, not for one family or model line. Where a brand- or model-specific page exists for your unit it is the more specific answer and it is linked above, so go there first if your machine is named. What is deliberately not here: element and fan ratings, sensor resistance tables, hinge and gasket part numbers, terminal block details and cabinet cut-out dimensions, all of which differ by family and belong on the page for that family.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
